Engine Lacks Power When Hot

[swanny1970]

Hi All

 

Hoping that someone will be able to help me out as I am going mad!!

 

Over the past several weeks the car has been intermittently losing power and I literally have to knock it down a gear and floor it to gain acceleration. This problem only happens when I have been driving a while and the engine gets hot (when initially started up, it drives great with no probs but after 15 mins of driving, the problem rears it's ugly head!) The car feels like it is losing power and drives very sluggish at times - jerky. When the problem is happening, I have to take off at 3000 rpm or the car just seems to go flat. When the problem happens when I am driving, the car starts jolting as if I am in the wrong gear and I have to floor it again. I suspected the MAF after reading posts on here and have tried several from a friend of mine who owns a secondhand parts shop. Had varying results, with some causing the car to cut out every time I stopped, to others working great for about an hour and then back to the way it was before. Disconnecting the MAF causes no change whatsoever. The engine also revs high when the Engine Idle Control Unit is connected, but this has been a problem I have had for almost a year. I have been driving this length of time with the Engine Idle disconnected and had no problems until a couple of weeks ago. Checked the coils, plugs, hoses etc and found one hose that was broken at the elbow. This is situated at the front of the engine and goes to the inlet manifold. Replaced this and still the same. Any help that anyone can give me on this would be greatly appreciated. Getting nagged by the kids to take them to see the lights at Blackpool and the thought of driving on the M6 with the car like this scares the living daylights out of me (plus, the lack of power on the car would mean that if I left today, I would probably arrive just as the lights were being switched off!!!)

 

Thanks in advance to anyone that can offer any help and advice.

 

Cheers, Peter

[mumof4]

Have you tried a MAF with the same part number as yours as there are different MAFS for different models/years fuel variants.It is always best to try the one that is required for your car rather than trying several from different cars.Plus are you sure the second hand ones arent foobed?

[swanny1970]

Hi Mumof4,

 

Thanks for your reply. Not sure that the ones I have tried aren't foobed (great word!) but all but one have been the same part number as mine. Driving with the MAF disconnected causes no change in the performance, does this point to anything else that you can think of?

 

Thanks in advance,

 

Cheers Peter

[NikpV]

Hi Mumof4,

 

Thanks for your reply. Not sure that the ones I have tried aren't foobed (great word!) but all but one have been the same part number as mine. Driving with the MAF disconnected causes no change in the performance, does this point to anything else that you can think of?

 

Thanks in advance,

 

Cheers Peter

 

dont think that the 2.3 suffers as much with maf problems as TDI's do, if its a problem when the engine is hot I would start looking at temperature sensors (not the same one as the gauge though there are 2 IIRC, does the 2.3 have a TMAP sensor (Temperature and manifold Pressure ) ??

[Stevoo]

2.3 are a bit funny when hot. get a local mechanic to plug a ecu reader into your ecu to get the air temp on intake. my uncle did this for me and the air was 56c on a summers day. so the hotter the air comming in or temp sensor not working car wont perform when its cold.

[chazhead]

I'd go with temp sensor as well.

 

When the car is cold & the ECU thinks it is cold the mixture is going to be rich, as the car warms the temp sensor should...urm sense this...and the ECU would lean off the mixture. If the sensor is 'foobed' then maybe the ECU thinks the engine is still cold and keeping the mixture rich, and a hot engine running on a rich mix is very sluggish, misses and will eventually conk out.

 

Where they are tho.....sorry I don't know.

[swanny1970]

Hi All

 

Thanks for your replies. Can I ask, is the temp sensor that you are talking about the one that is on the rubber hose that comes from the MAF to the Throttle Body? If so, I called Fords last night and they are only

[swanny1970]

Hi All

 

Thought I would post the results of my problem that now seems to be solved, incase other people are having the same issues.

 

The problem was being caused by a split crankshaft ventilation hose. It was only a small rubber elbow, that sits behind the exhaust on the engine block, but boy did it cause major problems to my driving! I also got the valve that joins onto one end of the tube with the other end going into the crankshaft. Drove around all afternoon, kangaroo free, loads of power and am one happy man!! Loads more miles for the fuel now, which can't be a bad thing! Also, as stated in my original post, I have been driving with the ISV disconnected for about a year now. After I fitted the rubber elbow today, I plugged the ISV back in and the engine and rpm were stable! Not been like this in a year. This small elbow sure caused a load of problems. If you have any symptoms like mine, I would suggest checking this as a cheap option before spending loads on more expensive parts. Thanks for all the help on this, hope that this may be able to help others out too. Fingers crossed this is a permanent fix, can't take it anymore!!!!!! :lol:

 

Cheers,

 

Peter

Edited October 10, 2007 by swanny1970